Connectivity Framework 4 : Connectivity Framework Layer
Delivery refers to the delivery aspects of the data including :
• Best-efforts delivery : An update is sent once , regardless of whether the receivers get it . Also called a fire-and-forget scheme , this is a form of “ at most once ” delivery . It is suitable when high-frequency periodic updates need to be distributed in a system and out-oforder or missing updates can be tolerated .
• Reliable delivery : An update is sent and also cached by the sender for later redelivery , in case receiver ( s ) don ’ t get it in a timely fashion . The amount of caching and timing can be configured based on the application and data flow requirements . Acknowledgements from a receiving endpoint can be automatic at the connectivity framework level , or may require explicit response from the application . This is a form of “ at least once delivery ”. It is suitable for low frequency status updates , events and notifications and also for commands when updates from a source are expected in-order .
In addition :
• Timeliness is the ability of the connectivity framework to establish end-to-end timing constraints , adaptively reconfigure to either guarantee specified timing or minimize timing violations , and to notify the application if a timing constraint has been violated .
• Ordering is the ability of the connectivity framework to present the data in the order it was produced , or received , and collate updates from different sources in the system .
• Durability is the ability of the connectivity framework to make data available to late joiners , and extend the lifecycle of the data beyond that of the source when so desired , and survive failures in the infrastructure .
• Lifespan is the ability of the connectivity framework to expire stale data .
• Fault tolerance is the ability of the connectivity framework to ensure that redundant connectivity endpoints are properly managed , and appropriate failover mechanisms are in place when an endpoint or a connection is lost .
The underlying transport layer will ultimately bound a connectivity framework ’ s performance and scalability limits . The connectivity framework should introduce minimal overhead in providing the data exchange QoS and should have minimal impact on the overall performance and scalability .
4.1.11 DATA SECURITY
A connectivity framework should provide the ability to ensure confidentiality , integrity , authenticity and non-repudiation of the data exchange , when so desired .
The connectivity framework security mechanisms should provide a means to :
• upon discovery , authenticate endpoints before allowing them to participate in a data exchange ,
• authorize permissions ( read , write ) granted to the endpoints participating in a data exchange , to ensure that endpoints cannot write or read data that they have not been given access to ,
IIC : PUB : G5 : V1.0 : PB : 20170228 - 31 -